Histological healing after grafting of bilayer artificial dermis in the oral environment

Kim, Min Jeong; Chung, Hyun Ju; Kim, Ok Su; Kim, Young Joon

Abstract

The autogenous free gingival graft is the most predictable procedure currently used to increase the width of the attached gingiva in periodontics. But the major disadvantage of the procedure is to create the multiple surgical wounds at both a donor site and a recipient site. The other problem is the limited amount of available graft material in oral cavity. Therefore, recent researches have been focused to develop the biomaterial to substitute the autogenous gingival tissue. The purpose of this study was to evaluate the histologic healing after grafting of bilayer artificial dermis, compared to the free gingival graft. Four non-smoking subjects (mean age, 32.5 years) in systemically healthy state and good oral hygiene were selected according to their particular needs for correction of mucogingival problems as suggested by Nabers(1966). The recipient sites were prepared through the procedure for the free gingival graft and were grouped according to the graft materials: Experimental group(n=5) - bilayer artificial dermis (Terudermis(R); Terumo Co. Japan) and Control group(n=6) - free gingival graft with autogenous palatal mucosa. Biopsies were harvested at 1, 2, 3 and 6 weeks postsurgery to evaluate histologically. At the third week in the experimental group and at the second week of in the control group, the grafts has been clinically stabilized on the recipient bed and the graft border has been blended into the surrounding tissue. In the experimental group after 1 week of grafting, the epithelial migration from the adjacent tissue to graft material was seen and after 3 weeks of grafting, the : nflmmation decreased, collagen layer of the artificial dermis was lost and the basement membrane of epithelium was formed. After 6 weeks of grafting, both groups demonstrated orthokeratinized epithelium and increased thickness of epithelial tissue and the rete peg formation, similar to the adjacent tissue. Histologic evaluation revealed a biologic acceptance and incorporation of the collagen layers of the graft tissue to the host tissue, without foreign body reaction. In conclusion, a bilayer artificial dermis is essentially similar to autogeneous free gingival graft in the correction of mucogingival problems, and has the advantages of decreased patient morbidity (no donor site) and availability of abundant amounts of graft material when needed.